/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.iceberg.orc;

import org.apache.hadoop.hive.ql.exec.vector.ColumnVector;
import org.apache.iceberg.FieldMetrics;

import java.util.stream.Stream;

public interface OrcValueWriter<T>
{
    /**
     * Take a value from the data value and add it to the ORC output.
     *
     * @param rowId  the row in the ColumnVector
     * @param data   the data value to write.
     * @param output the ColumnVector to put the value into
     */
    default void write(int rowId, T data, ColumnVector output)
    {
        if (data == null) {
            output.noNulls = false;
            output.isNull[rowId] = true;
            nullWrite();
        }
        else {
            output.isNull[rowId] = false;
            nonNullWrite(rowId, data, output);
        }
    }

    void nonNullWrite(int rowId, T data, ColumnVector output);

    default void nullWrite()
    {
        // no op
    }

    /**
     * Returns a stream of {@link FieldMetrics} that this OrcValueWriter keeps track of.
     */
    default Stream<FieldMetrics<?>> metrics()
    {
        return Stream.empty();
    }
}
